Police are increasing their patrols in Arrowtown after a spike in complaints from residents about vandalism and alcohol-related acts by teenagers in the past few weeks.
Sergeant Chris Brooks, of Queenstown, said police had received "numerous reports" of antisocial behaviour at night and at weekends, including vehicle and property damage, noise and poor driving behaviour.
The youths, some as young as 14, were coming from all over the Queenstown area.
Police had "moved on" groups of up to 20 young people, some with a large amount of alcohol with them, from trouble spots in and around the township, Sgt Brooks said.
Although some matters were still being investigated, police had not charged anyone or issued formal warnings.
The parents of some teens had been contacted, most of whom had been "great to deal with", he said.
Police were also concerned about some small fires in the area, which prompted callouts of Arrowtown volunteer firefighters.
"Safety is our primary concern, which includes prevention advice to parents and young people who may not be cognisant that their behaviour places them at heightened risk."
He encouraged parents to speak to their children about where they were going and who they were meeting, and to be "extremely cautious" about giving young people alcohol without appropriate supervision.
